The Bottom Finding Deep Sea Pinger is a sophisticated acoustic transmitter which continuously shows height above bottom for oceanographic devices such as corers, dredges, water sampling bottles and plankton nets that are lowered to any depth. The pinger can also be used as an acoustic beacon for site relocation. The pinger features a proprietary, fully pressure-compensated, acoustic projector enclosed in stainless steel. It is virtually immune to handling or impact damage a feature of particular importance for sea-going equipment.

The output frequency of the pinger is precisely 12 kHz to match transducers and recorders found on most oceanographic ships. Both the 12 kHz ping frequency and the one-second repetition rate are crystal controlled. The pulse has switch selectable lengths of 0.5, 2, and 10 milliseconds to enable variation of the bottom echo resolution. The pinger incorporates an event-signalling feature which doubles the pulse repetition rate from one to two pulses per second when the pinger is tilted more than 70 degrees from vertical. The circuitry is mounted on two plug-in printed circuit boards and powered by a battery module containing manganese-alkaline "C" cell batteries.

The pinger is enclosed in a full ocean depth, stainless steel housing held closed by the Benthos single-bolt closure system. The housing is equipped with convenient handles and pad eyes. The external on/off switch can be operated with a coin or screwdriver.